The primary objective is to evaluate the persistence of bactericidal antibodies in adolescent subjects who completed study V59P6 in which they received either Novartis Meningococcal (MenACWY) Conjugate Vaccine or Licensed polysaccharide Men ACWY vaccine (Menomune®). The study will also enroll age-matched subjects who have never received any other meningococcal vaccine (naïve subjects) to serve as an additional control group.